In recent years, a wide proliferation of wireless systems and the use of software defined radio technologies have lead to the employment of heterogeneous networks, allowing service providers to use networks that are most efficient for a particular type of service. An example is the Internet, which is now a common, core network that interconnects various wireless access points. However, in the wireless realm, users of wireless networks are limited to the bandwidth and range of the protocol used, whether the protocol is IEEE 802.11, Code Division Multiple Access (CDMA) 1xRTT (CDMA2000), CDMA 1xEV-DO, Wideband Code Division Multiple Access (W-CDMA), Enhanced Data rates for GSM (Global System for Mobile Communications), Evolution (EDGE), General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), Worldwide Interoperability for Microwave Access (802.16, WiMAX), High-Speed Downlink Packet Access (HSDPA), satellite, Cellular Digital Packet Data (CDPD), Integrated Digital Enhanced Network (iDEN), or the like. In addition to bandwidth (downlink and uplink) and range limitations, a given wireless channel can also be subject to considerable interference and coverage limitations.
A major challenge presently facing the wireless industry is to efficiently utilize scarce wireless resources. On the one hand, limitations in available resources like spectrum, bandwidth, latency, and energy are becoming major bottlenecks. On the other hand, the proliferation of wide-band applications, such as real-time applications that send and receive high-quality audio and video, requires increased bandwidth and better Quality-of-Service (QoS). Today's wireless and wired networks are designed for specific service and applications, but wireless networks, while supporting mobility, usually don't satisfy the type of service supported by wired networks. Further, applications designed for wired networks have bandwidth requirements well beyond the capabilities of commercially available technologies, within the boundaries of applicable FCC regulations. A major overhaul of the present infrastructure to support such requirements would therefore be very costly and would still result in limitations.
Due to the limitations of present wireless infrastructure, it would be very advantageous in numerous sectors (e.g., commercial, government, civilian) to provide a system for allowing communication over multiple, heterogeneous wireless channels, as well as wired channels. For example, first responders, such as municipal law enforcement agencies and fire departments, have a need for improving the size of the area of coverage for their wireless communications requirements. Presently, bandwidth limitations, unreliability, lack of mobility support, and poor performance in general of wireless access networks prevent first responders from using wide-band applications that would allow them to perform their jobs more efficiently. The current practice for first responder agencies is to build new communications towers to reduce or eliminate poor coverage areas within their respective jurisdictions. Depending on the area (e.g., a rural area), this approach could require the installation of numerous towers, which is an inherently expensive and time-consuming operation. While tower construction may improve coverage, such an approach does not provide broadband data capability since current first responder standards for wireless communication are primarily oriented towards voice services. Because of this drawback, first responder agencies are also considering WiFi (IEEE 802.11) hot spots across their jurisdictions by installing additional towers. However, this is an expensive proposition, and officers would have to drive to such sites for high-speed data services, resulting thereby in a potential inconvenience and a source of inefficiency.
Other agencies are considering upgrading or deploying commercial cellular data services, such as 1xRTT, 1xEV-DO (offered by CDMA operators) or EDGE/GPRS (offered by GSM operators), which offer better bandwidth and allow for dedicated data channels. However while this would improve the quality of the communications medium (in terms of coverage, reliability, and bandwidth), such upgrades would still be unable to meet the requirements for mission-critical operations. In addition, the bandwidth offered by each operator is not sufficient to convey critical information, such as demanding video feeds and real-time traffic including two-way audio or video. In the commercial sector, VoWLAN (Voice over Wireless Local Area Networks) is being deployed in large cities to provide a cheap and high-bandwidth communication channel. The fundamental problems with these services are cost and limited access. In order to exploit VoWLAN services, new “dual-mode” devices need to be deployed. Also, these mobile units are restricted to the coverage of the WLAN used for operation. As the user moves out of the area covered by the wireless networks, calls are typically dropped, until they can be re-established on another wireless network. This is not suitable for fast-moving operations, such the ones conducted by public safety agencies. Further, for wireless applications, the need for QoS mechanisms is greater due to scarce resources, unpredictable available bandwidth, and variable error rates.
Accordingly, what would be desirable, but has not yet been provided, is a multi-access access terminal for communicating over multiple, heterogeneous (e.g., wired and wireless) communication channels, wherein a mobile client can simultaneously aggregate multiple connections to heterogeneous access points and/or ad-hoc network terminals to increase capacity and/or efficiency. An improvement in the collective QoS of the aggregated channels is a direct result, due to the heterogeneous environment and the characteristics of the channels.